Such a turnoff! Anderson Cooper revealed that Andy Cohen broke his “cardinal rule” of dating during a Wednesday, November 30, appearance on Watch What Happens Live. See what he had to say in the video above!

According to the CNN news anchor, 49, he and pal Cohen, 48, almost went on a blind date several years ago. However, the Bravo head honcho ruined his chances for a romantic night out because he came off just a tad too interested in Cooper’s famous socialite mother, Gloria Vanderbilt.

"Andy and I were first set up on a blind date, which never happened because we had a phone call and after two minutes I said, 'I’m not dating this guy,'" Cooper recounted to a red-faced Cohen and fellow guest and BFF Kelly Ripa. "He broke my cardinal rule … he mentioned my mom within the first four sentences of meeting me."

Later on in the show, Cooper’s love life became a hot topic again when a viewer sent in a Facebook question asking if the openly gay broadcaster had ever “been with a woman.”

"I’ve gone on a date or two with a woman," a bashful Cooper answered, to which Ripa, 46, pressed, “That’s not answering the question!”

The Anderson Cooper 360 personality elaborated just a bit more about his encounters with members of the opposite sex, saying, "I don’t think I’ve done more than kissing a woman, no, yes.”

“You don’t think?” a skeptical Ripa asked.

Cooper clarified, “No, I mean, I know. I haven’t done more than kissing.”

Watch the video above. Watch What Happens Live airs on Bravo Sunday through Thursday at 11 p.m. ET.

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